build: Add dist script

This script will vendor the Rust dependencies
of the app so that our tarballs can be built
offline.

build-aux/meson/dist-vendor.sh

@@ -0,0 +1,9 @@
+#!/bin/sh
+export DIST="$1"
+export SOURCE_ROOT="$2"
+
+cd "$SOURCE_ROOT"
+mkdir "$DIST"/.cargo
+cargo vendor | sed 's/^directory = ".*"/directory = "vendor"/g' > $DIST/.cargo/config
+# Move vendor into dist tarball directory
+mv vendor "$DIST"

meson.build

@@ -66,3 +66,9 @@ gnome.post_install(
   glib_compile_schemas: true,
   update_desktop_database: true,
 )
+
+meson.add_dist_script(
+  'build-aux/meson/dist-vendor.sh',
+  join_paths(meson.project_build_root(), 'meson-dist', meson.project_name() + '-' + meson.project_version()),
+  meson.source_root()
+)